Improvement in the preparation of hides for tanning



UNITED STAT S PATENT? o es.

' GEORGE W. HATCH, OF PRINCETON, ILLINOIS. I

Specification forming part of Letters Patent No. 15,736. dated September16, 1856.

To all whom it may concern: 7

Be it known that I, GEORGE W. HATCH, of Princeton, Bureau county,Illinois, have invented a new and Improved Mode of Preparing Hides forRapid Tanning into Leather; and I do hereby declarethat the following isa full and exact description thereof.

This process of preparing hides and of turnin g them into leather isperformed by the use of smoke of wood or equivalent eombustibles,applied and described in the following manner: The nature of myinventionconsists in smokinghides after being unhaired and batedor previous toputting them into tan,which changes the nature of the gelatine into anadmirable condition for the rapid reception of tannin, and at the sametime preserving the full texture and strength of the fiber, thusenabling me to tan calf-skin into leather in from two to twelve days,upper and collar leather in from V eight to twenty days, and otherleather in a proportionate time, according to the thickness. Havingbecome satisfied from the general expression and personal experience ofthe inetficiency of any late-patented system of tanning of generalapplication, and still feeling the great want of that desideratum solong sought for of obtaining a system ofquick tanning with good resultsby cheap and simple means of general application, I have used everyexertion in trying, if possible, to obtain that method. In 18341 had noless than twelve dift'erentcourses in operation at once. I discoveredthree favorableout of the twelve, selected the best out of the three,perfected in tanning by it for about one year, and liked it better thanany patented yet; but I found it like its predecessors-400 uncertain forgeneral use. I Have become well satisfied that any chemical mixtures orcompounds tend 1n ore or less to destroy tanning or injure the leather,because the hide,in the first place, must be prepared to receive thegreat shock of so powerful and rapid tanning. In the latterpart ofOctober, 1855, I made the discovery that by smoking the hides and thenhandling them in sumac, bran, and water for half a day, and thenputtingthem into alum, tan, and sumac, the tan struck through heavyupper in three days. I am gratified to say that on a thorough test withthat and othertannings it has responded to my fullest desires. I havealso realized the fact that hides prepared in this way preserve thegelatine inv such condition as to keep longer even in poor, weak liquorvoid of tan. I have used smoke from various kinds of combustibles, allproducing the desired effect. y

Some of the great beneficial results in this kind of tanning are these:

First. I can with a small capital compete with any other tanner underany other system yet discovered, either in the country, where plenty ofbark can be had, or in the great prairies of the great West.

Secondly. I can turn my capital five times every once that anyone elsecan under any system yet invented, having good results in general.

Thirdly. 1 defy the world to produce better or more durable leather thanis produced by this system of tanning: By this system of smoke inconnection with tanning it enables meto use terra-japonica tannin, withor without other aids in the tannin g,with perfect good results.

Fourthly. To tan in these vastprairies where there is no tan-bark inmuch less time successfully in competition with manufactories in tanbarkdistricts.

Fifthly. That this principle of smoke, the

great desideratum, is applicable in bark-tanning the-world over, and interra-japoniea or other tanning.

Sixthly. By it I have been able to bring eight pounds of prepared hidethrough in thirty-six hours; cowhide, upper leather, and collarleatherin eight days, making good leather, yet I prefer from four to twelvedays time for tanning the same.

The leather which I have tanned by this new system has been well testedand given good satisfaction. The calf-skin I sent you was tanned throughin moderate tanning in ten days; but was left in the tan four dayslonger to fill up perfectly, then finished.

To enable others skilled in the art to use my invention, I will proceedto describe the mode and operation, which is convenient, simple, andsure in the desired effect, and applicable to all general species oftanning, therefore admirably adapted and convenient for universal andgeneral use, even by tanners of ordinary skill.

I bate my hides in the usual way, either in hen-bate or wheat-bran, (Iprefer bran, as it leaves the hide more plump,) until the lime isthoroughly worked out. After working off the last time, I rinse in cleanwater to plump up and open the hide fully wet, in order while smokingthe grain may not become too dry, as well to rinse off alluncleanliness. Then hang up in a tight smoke-room sufficiently large to'hangup by butt and neck, grain-side out. Then make a smoke in such amanner that the hides may not become heated from the fire. Smoke upperand collar leather hides six hours other hides time according tothickness. Then take them out and soak them in clean water one hour, toassure the hides a fully-wet condition before coming in contact withtan. Then put them into tan-ooze of moderate strength, stir and handleoften until the grain is colored even and struck through. Then increasethe strength of the ooze by tannin from day to day till the hides aretanned.

To get a light colorin the terra-japonica or hemlock ooze, I add alittle sumac in the first handler in such proportion as half a pound perside for upper-leather; for heavy leathersuch as harness and soleleather-after being prepared in the usual way, should be smoked sixhours, then soaked in clear water one hour, then smoked again six hours,and soaked and put into tan, as above stated.

Now, I wish it distinctly understood that I do not claim the use ofpyro-ligneous acid as such, but confine my claim to the use of smokefrom wood or other equivalent combustibles in the preparation of hidesfor rapid tanning, as above set forth.

GEO. W. HATCH.

Attest MARTIN BALLoU, J USTUS BURR.

